Add Compile-time Conditionals Chapter

[rhagenson]

As previously discussed in #210 and #216, there is a need for a compile-time arguments chapter. Currently a few compile-time options are discussed in Appendices/Compile Arguments (as #210 seeks to change), however there are a great deal more options to cover such as those in discussed in #216: compile_error, compile_intrinsic, and iftype.

The two referenced issues still stand as necessary fixes in my mind as both require a compile-time flag to be used, named --debug for use of Debug and --define for use of ifdef. This issue thread is focused on discussion surrounding the non-flagging options which otherwise do not have a dedicated place for their inclusion.